Given that Bruce went on and won a Stanley Cup the season after he was let go is some egg on the face of Cam and Don. For me, one constant whatever the overall play of the team has been, is that the powerplay has been subpar. It's been an issue for years, and there is one constant denominator there. Why that hasn't been addressed is a real head-scratcher.
I suspect you're really talking about a level or two above the coaching staff, though. All I can say there is that the team has, for some time now, had problems starting games on time, and rising to the occasion, whether it's closing out a playoff series, or a single game. I don't think that is largely on the coach because it happened under Bruce, too. That seems to say it's a roster issue, and that points to a problem up the chain.
What I don't know is how much is Don and how much is Cam- how often does Cam override Don in these decisions, or perhaps acquiesce when he disagrees?